Research is proposed to test theoretical models of social behavior in a population of anubis baboons (Papio anubis) under natural conditions. Approximately 200 subjects will be trapped, marked for permanent identification, and biomedical samples will be taken providing baseline information on baboon growth, development, and morphology. Most importantly the biomedical portion of the study will permit the determination of genetic relationships among the subjects through an analysis of serum protein polymorphisms and other genetic markers. Such data will permit us to conduct a detailed investigation of how nonhuman primate behavior is mediated by kinship for the first time. Models of optimal social behavior are discussed with respect to inclusive fitness, life history strategies, feeding strategies, parental investment, aggressive competition and social dominance. Hypotheses derived from these models are formulated, and the experimental procedure by which they can be tested in a study of ecology and social behavior is discussed.